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Mechanical Engineering :: Steam Nozzles and Turbines

  1. On Mollier chart, flow through turbine is represented by

  2. A.

     Horizontal straight line

    B.

     Vertical straight line

    C.

     Straight inclined line

    D.

     Curved line


  3. A stage, in reaction turbine, is represented by

  4. A.

     Number of casing

    B.

     Number of entries of steam

    C.

     Number of exits of steam

    D.

     Each row of blades


  5. At very low temperature, the melting and boiling temperatures become equal. This temperature is

  6. A.

     373°K

    B.

     273.16°K

    C.

     303°K

    D.

     0°K


  7. Carbonization of coal is the process of

  8. A.

     Pulverizing coal in inert atmosphere

    B.

     Heating wood in a limited supply of air at temperatures below 300°C

    C.

     Strongly heating coal continuously for about 48 hours in the absence of air in a closed vessel

    D.

     Binding the pulverized coal into briquettes


  9. When the inlet pressure of steam is equal to the exit pressure, then

  10. A.

     There is a pressure drop in the nozzle

    B.

     Fluid flows through the nozzle

    C.

     Pressure drops and fluid flows through the nozzle

    D.

     There is no pressure drop and fluid does not flow through the nozzle


  11. The impulse reaction turbine has its driving force

  12. A.

     As an impulsive force

    B.

     As a reaction force

    C.

     Partly as an impulsive force and partly as a reaction force

    D.

     None of the above


  13. The efficiency of reaction turbine is maximum when (where α = Angle made by the absolute velocity ‘V’ at inlet)

  14. A.

     Vb = 0.5 V cosα

    B.

     Vb = V cos α

    C.

     Vb = 0.5 V² cosα

    D.

     Vb = V² cos α


  15. The function of injector used in small capacity boilers is to

  16. A.

     Create vacuum

    B.

     Inject chemical solution in feed pump

    C.

     Pump water, similar to boiler feed pump

    D.

     Add make up water in the system


  17. Stoichiometric quantity of air is the

  18. A.

     Air present in atmosphere at NTP conditions

    B.

     Air required for complete combustion of fuel with no excess air

    C.

     Air required for optimum combustion so as to have reasonable excess air

    D.

     Air required to convert CO into CO₂


  19. Which is not correct statement about pulverized fuel firing?

  20. A.

     High burning rate is possible

    B.

     Heat release can be easily controlled

    C.

     Fuel burns economically

    D.

     It is the best technique for burning high ash content fuel having low fusion ash